Expand table issues after Merging Queries

Good afternoon everybody. 

I am having a strange issue with getting different values when expanding 2 merged Queries. 

The queries have been successfully merged and when verifying values before expanding everything seems to be in order see below- 

Before expanding the table - all the values are correctly displayed.

After expanding the table using Expand table icon on the Headers:

These null values should contain values in previous image

No clue why this is happening. 

I've Cleaned, Trimmed and Uppercased the column used to merge, set them both to to Text Type. 

Any help with this would be very useful. 

Thank you in advanced. 

Best regards, 

Ricardo.